1. Field of the Invention
This invention relates to power wrenches and in particular to an engine-powered torque wrench having a loop handle that is orthogonal to a torque handle and in a plane parallel to an axis of a torque-wrench shaft.
2. Relation to Prior Art
Powered torque wrenches generally are tethered to electrical or pneumatic sources of operating power. They do not have non-tethered engine power with a convenient positioning handle in operative relationship to a torque handle in a manner taught by this invention.
One of the large uses of torque wrenches is for tightening and loosening lug nuts on wheels of highway trucks and trailers where electricity or high-pressured air are not available. Previously for this and other torque-wrench applications, hand wrenches have been used. Changing dual wheels on highway trucks with hand-power wrenches is so difficult for truck drivers on roadsides that the dual wheels of flat tires are often not changed. Instead, they are ruined by being driven flat to a repair facility. The cost of a ruined tire or the cost of repair service remote from a repair facility can be about as much as the cost of this engine-powered torque wrench with which numerous wheels can be changed.
There are other uses for this engine-powered torque wrench with comparable economic advantages. It is highly advantageous for use anyplace where electricity or pneumatic power are not readily available for either an electric-powered torque wrench or a pneumatic torque wrench which might be available. Versatility of easy use anywhere renders this invention a torque wrench of choice, even where electricity and/or air power are available.
Examples of most-closely related known but different powered tools are described in the following patent documents:
Objects of patentable novelty and utility taught by this invention are to provide an engine-powered torque wrench which:
has power remotely from electrical or other fixed-site power sources;
can be positioned conveniently and accurately from any angle;
is optionally right-hand or left-hand operable;
has effective leveraging in opposition to rotational output power; and
has convenient throttling at a torque handle.
This invention accomplishes these and other objectives with an engine-powered torque wrench having a loop handle that is orthogonal to a torque handle. The engine-powered torque wrench has a heat engine which rotates a tool shaft. The heat engine has a rotary axis that is collinear to a shaft axis of the tool shaft. The loop handle is adapted to be hand-grasped by a first hand of a user for primary support of a system weight of the engine-powered torque wrench while selectively positioning a desired tool on a targeted item. The torque handle is adapted to be hand-grasped by a second hand of the user for secondary support of the system weight while simultaneously using the second hand for assisting in positioning of the tool, leveraging against rotational moment of the tool shaft and throttling the heat engine.
The engine-powered torque wrench is adapted for either right-handed or left-handed use and for either right-side access or left-side access to a wrench-targeted item. For right-handed use and for right-side access to the wrench-targeted item, the torque handle is positioned on a right side of the wrench-targeted item, the loop handle is grasped by the left hand and the torque handle is grasped by the right hand of the user with the user facing the wrench-targeted item. For left-handed use and for left-side access to the wrench-targeted item, the torque handle is positioned on a left side of the wrench-targeted item, the loop handle is grasped by the right hand and the torque handle is grasped by the left hand of the user with the user facing the wrench-targeted item.
The engine-powered torque wrench is adapted for selectively vertical or horizontal orientation of the rotary axis and the shaft axis in accordance with desired objectives in relation to the targeted item. For the selectively vertical or horizontal orientation in relationship to a targeted item that is vertically below the loop handle, the loop handle is adapted to be grasped by a first hand of the user at a position on the loop handle that is vertically higher than the targeted item, while the torque handle is grasped by the second hand of the user and the axis of the tool shaft is collinear to targeted rotation of the tool in relation to the targeted item.